[rfc] frame->frame => frame->addr && frame->base()

From: Andrew Cagney <ac131313 at cygnus dot com>

To: gdb at sources dot redhat dot com

Date: Thu, 11 Apr 2002 16:56:08 -0400

Subject: [rfc] frame->frame => frame->addr && frame->base()

Hello,
This comes from DanielB's and my discussion about dwarf2 CFA and
dwarf2's frame_base vs GDB's frame->frame.
An executive summary is that the two dwarf2 frame concepts (CFA and
frame_base) do not go into one GDB frame (frame->frame).
Because of this, I'd like to propose that the frame object have both:
struct frame_info
{
...
// An ISA/ABI specific address within the ``specified frame'' that is
constant throughout the lifetime of the frame. This address is used by
GDB as a handle to identify this frame. This field must be initialized
as part of the creation of a frame object. (see dwarf2 CFA)
CORE_ADDR addr;
// High level language concept of the base address of a frame. Often
refered to as ``frame_base'' or ``frame pointer''. This value should
only be computed on-demand. It is strongly recommended, though, that
implementations cache the computed value in the frame cache. The method
is initialized as part of the frame objects creation. The default
method returns frame->addr. (see dwarf2 DW_AT_frame_base)
CORE_ADDR (*base) (struct frame_info *frame);
...
}
Thoughts?
Andrew